And no, e.g. Ubuntu doesn't include Ruby or Git in default installation, nor FreeBSD.
Convenience to development should be measured by how easy it is to install/access development tools when you need them -- such as how well the package manager work, not how much stuff the base system come with.
Actually, I believe you can install Ruby/Git on Ubuntu install if you toggle Development tools. But anyone doing serious Ruby development will use rvm/docker.
Even when Ruby was included in Lion, nobody developing Ruby apps could use the vendor-supplied stuff. I remember this from back in 2008. There were countless blog articles telling you to download Ruby and compile. The situation from a decade ago caused a ton of pain in bootstrapping a developer setup.
I believe that is a consequence of macOS being built with BSD foundations. They're there. But let's not pretend macOS *nix/POSIX stuff is great; there's a reason that MacPorts exists.
I'd argue that Ubuntu does offer greater. Let's not pretend Xcode is a good IDE, either. I can't even recall the number of times I had my project crash on me.